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At least 19 recordsLinked to original sources
PubMed1963

A study of normal heart sounds, heart size, arterial pressure and electrocardiograms from infancy to early adulthood in one male and one female.

This study forms part of a project to define the range of normal for heart sounds and murmurs. Using the method of writing quantitative symbol phonocardiograms, data were collected on one female and one male subject from earliest infancy to adulthood (aged 27 and 25). Serial measurements of heart size, arterial pressure and records of electrocardiograms and electrophonocardiograms were made. The heart sounds are shorter and somewhat less loud under the age of two years than later. Physiologic splitting of the first and second sounds, a physiologic systolic murmur, the appearance and disappearance of a third sound are shown in the illustrations which epitomize this study. These longitudinal studies of age period changes in the electrocardiogram reveal what has been learned from the horizontal studies. The shape of the cardiac silhouette as recorded between the ages of 5 and 8 years seems to predict the adult shape. The adult type of arterial pressure became established in the early teens.

Adolescent↗
PubMedDate not supplied

A wavelet-based reduction of heart sound noise from lung sounds.

Heart sounds produce an incessant noise during lung sounds recordings. This noise severely contaminates the breath sounds signal and interferes in the analysis of lung sounds. In this paper, the use of a wavelet transform domain filtering technique as an adaptive de-noising tool, implemented in lung sounds analysis, is presented. The multiresolution representations of the signal, produced by wavelet transform, are used for signal structure extraction. In addition, the use of hard thresholding in the wavelet transform domain results in a separation of the nonstationary part of the input signal (heart sounds) from the stationary one (lung sounds). Thus, the location of the heart sound noise (1st and 2nd heart sound peaks) is automatically detected, without requiring any noise reference signal. Experimental results have shown that the implementation of this wavelet-based filter in lung sound analysis results in an efficient reduction of the superimposed heart sound noise, producing an almost noise-free output signal. Due to its simplicity and its fast implementation the method can easily be used in clinical medicine.

Adult↗
PubMed1981

[Heart sounds and heart murmurs in progressive muscular dystrophy of Duchenne type (author's transl)].

Phonocardiographic and echocardiographic investigation was performed in patients with progressive muscular dystrophy of Duchenne type (PMD). The clinical materials consisted of 90 patients with PMD (aged 8 to 21 yrs, a mean of 14.5), and 90 normal subjects (aged 6 to 19 yrs, a mean of 11.7). The patients with PMD were classified into 8 stages from the mildest, S(1), to the severest, S(8), according to Swinyard-Deaver' criteria. In the 90 normal subjects the diminished first heart sound was noted in 12 cases (13.3%), presystolic murmurs in 4 cases (4.4%), and diastolic rumbles in 9 cases (10%), whereas, in the patients with PMD the diminished first heart sound was noted in 47 cases (52.2%), presystolic murmurs in 41 cases (45.6%), and diastolic rumbles in 44 cases (48.9%). There was a significant difference in the incidence of the above-mentioned three phonocardiographic findings between the PMD patients and the normal subjects. But there was no significant difference in the incidence of a systolic click between these two groups. The incidence of the diminished first heart sound increased with the progress of Swinyard-Deaver' classification. A presystolic murmur was observed with the highest incidence in the stage of S(8). The incidence of a rumble was also augmented with increasing severity of the disorder from the stages of S(1) to S(7), but decreased in S(8). Another attenpt was made to relate the phonocardiographic findings to those of the echocardiogram. In the cases with anterior mitral leaflet fluttering, there were diastolic rumble in 69% whereas 16.7% of the patients without anterior mitral leaflet fluttering had diastolic rumbles. In two-dimensional echocardiography, the anterior and posterior mitral leaflets looked like pennants fluttering in the wind. All these observations positively indicate that anterior mitral leaflet fluttering was closely associated with the genesis of rumbles. Consequently, it can be concluded that the diminished first heart sound, presystolic murmurs and diastolic rumbles might be useful clinical signs in the assessment of the myocardial involvement in PMD.

Adolescent↗
PubMed1998

The physiologic cause of swallowing sounds: answers from heart sounds and vocal tract acoustics.

A hypothetical discussion of the cause of swallowing sounds is presented. It is suggested that the pharynx contains a number of valves and pumps that produce reverberations within the pharynx to generate swallowing sounds. As heart sounds are propagated via vibration of muscles and valves, it is further suggested that an analogy exists between the generation of heart sounds and swallowing sounds. This new theory is known as the cardiac analogy hypothesis. The inability of the current literature to explain the cause of swallowing sounds is seen to limit the diagnostic potential of cervical auscultation for dysphagia assessment. Future investigators are encouraged to prove or disprove the cardiac analogy hypothesis.

Acoustics↗
PubMed1984

Frequency spectra of the first heart sound and of the aortic component of the second heart sound in patients with degenerated porcine bioprosthetic valves.

To determine the usefulness of the frequency of heart sounds in the assessment of porcine bioprosthetic valve degeneration, frequency spectra of phonocardiograms of the first heart sound and the aortic component of the second sound were analyzed in 31 patients with degenerated porcine bioprosthetic valves. Comparisons were made with 35 control patients whose valves were inserted 1 month or less. Among 23 patients with degenerated porcine bioprosthetic valves in the mitral position, the dominant frequency of the first heart sound was 95 +/- 11 Hz, which exceeded the first sound in 18 controls (51 +/- 3 Hz) (p less than 0.01). The degenerated mitral porcine bioprosthetic valves of 14 patients showed calcification or fibrosis and the first heart sound in these patients was 115 +/- 16 Hz, which exceeded that of control subjects (p less than 0.001). The degenerated mitral porcine bioprosthetic valves of 9 patients showed torn leaflets only, and the first heart sound in these patients was 64 +/- 9 Hz, which did not differ from that of control subjects. In the aortic position, 8 valves were degenerated and the aortic component of the second sound was 109 +/- 12 Hz, which was higher than that in 17 control subjects (63 +/- 4 Hz) (p less than 0.001). Only 2 of these degenerated valves showed tears unaccompanied by calcific deposits or fibrosis, and the frequencies were comparable to that of control subjects. These observations indicate that the frequency of heart sounds in patients with degenerated porcine bioprosthetic valves becomes abnormally elevated when degeneration is accompanied by calcification or fibrosis, which causes the cusps to stiffen.

Aortic Valve↗
PubMed1984

Spectral analysis of heart sounds: relationships between some physical characteristics and frequency spectra of first and second heart sounds in normals and hypertensives.

Frequency analysis of heart sounds has been gaining recognition as a possible indicator of several heart and valve diseases, although a comprehensive study of normal heart sounds has not been published. Relating the frequency content of normal heart sounds to certain physical characteristics surrounding the generation of these sounds could lead to a valuable diagnostic tool and give a better understanding of the mechanism of heart sounds production. In this study, the first and second heart sounds from seventy-four normal, and seven hypertensive volunteers were recorded, digitized and analysed using a Fast Fourier Transform algorithm. Statistical analysis was used to relate physical characteristics (sex, blood pressure, and body surface area) of the subjects to the frequency content of normal heart sounds and to compare normal and hypertensive heart sounds. Statistical analysis showed that the major concentration of energy, for both first heart sound (S1) and second heart sound (S2), is below 150 Hertz (Hz) which may indicate that both sounds are caused by vibrations within the same structure, possibly the entire heart. However S2 spectra have greater amplitude than S1 spectra above 150 Hz, which may be due to vibrations within the aorta and pulmonary artery. Relationships observed between body surface area, sex, blood pressure, and the frequency content of heart sounds indicate that as heart size increases, the amplitude of the frequency coefficients above 150 Hz decreases. These observations were more identifiable in the S1 spectra than in the S2 spectra, possibly because the S2 higher frequency components may mask subtle changes in the S2 spectra caused by heart size changes. However, when the changes in heart size are significant, as in hypertension or increased body surface area, trends in the S2 spectra can be observed.

Adolescent↗
PubMed2001

Prognostic importance of elevated jugular venous pressure and a third heart sound in patients with heart failure.

BACKGROUND: The independent prognostic value of elevated jugular venous pressure or a third heart sound in patients with heart failure is not well established. METHODS: We performed a retrospective analysis of the Studies of Left Ventricular Dysfunction treatment trial, in which 2569 patients with symptomatic heart failure or a history of it were randomly assigned to receive enalapril or placebo. The mean (+/-SD) follow-up was 32+/-15 months. The presence of elevated jugular venous pressure or a third heart sound was ascertained by physical examination on entry into the trial. The risks of hospitalization for heart failure and progression of heart failure as defined by death from pump failure and the composite end point of death or hospitalization for heart failure were compared in patients with these findings on physical examination and patients without these findings. RESULTS: Data on 2479 patients were complete and analyzed. In multivariate analyses that were adjusted for other markers of the severity of heart failure, elevated jugular venous pressure was associated with an increased risk of hospitalization for heart failure (relative risk, 1.32; 95 percent confidence interval, 1.08 to 1.62; P<0.01), death or hospitalization for heart failure (relative risk, 1.30; 95 percent confidence interval, 1.11 to 1.53; P<0.005), and death from pump failure (relative risk, 1.37; 95 percent confidence interval, 1.07 to 1.75; P<0.05). The presence of a third heart sound was associated with similarly increased risks of these outcomes. CONCLUSIONS: In patients with heart failure, elevated jugular venous pressure and a third heart sound are each independently associated with adverse outcomes, including progression of heart failure. Clinical assessment for these findings is currently feasible and clinically meaningful.

Aged↗
PubMed1992

Implications of third heart sounds in patients with valvular heart disease. The Veterans Affairs Cooperative Study on Valvular Heart Disease.

BACKGROUND: The presence of third heart sounds in patients with valvular heart disease is often regarded as a sign of heart failure, but it may also depend on the type of valvular disease. METHODS: We assessed the prevalence of third heart sounds and the relation between third heart sounds and cardiac function in 1281 patients with six types of valvular heart disease. RESULTS: The prevalence of third heart sounds was higher in patients with mitral regurgitation (46 percent) or aortic regurgitation (28 percent) than in those with aortic stenosis (11 percent) or mitral stenosis (8 percent). The left ventricular ejection fraction was significantly lower (P less than 0.001) when a third heart sound was detected in patients with aortic stenosis (0.38, vs. 0.56 in those without third heart sounds) or mixed aortic valve disease (0.40 vs. 0.55). However, the ejection fraction was only slightly lower in patients with mitral regurgitation and third heart sounds (0.51 vs. 0.57, P = 0.03). The pulmonary-capillary wedge pressure was higher (P less than 0.001) when a third heart sound was detected in patients with aortic stenosis (18.6 mm Hg, vs. 12.1 mm Hg in those without third heart sounds). There was no association between the wedge pressure and third heart sounds in patients with mitral regurgitation. The prevalence of third heart sounds increased with the severity of mitral regurgitation. CONCLUSIONS: In patients with mitral regurgitation, third heart sounds are common but do not necessarily reflect left ventricular systolic dysfunction or increased filling pressure. In patients with aortic stenosis, third heart sounds are uncommon but usually indicate the presence of systolic dysfunction and elevated filling pressure.

Adult↗
PubMed1990

Clinical value of the pitch of the third heart sound in ischemic heart disease.

The study investigates the genesis of the third heart sound (S3) in ischemic heart disease based on a mass-spring model. In such a system, the natural frequency of vibration, Fn, depends on the elastic constant, k, and the mass, m, according to the following relationship: Fn = 1/2 pi square root of k/m. To identify the cardiac structures representing k and m, the correlations between the energy of the S3 spectrum and the echocardiographic parameters were searched for. The results are consistent with a model in which k is represented by the thickness of the left ventricle and m by its blood content. The k/m ratio emerges as an important determining factor of the acoustic quality of S3, and yields information on the dysfunction of the left ventricle in ischemic heart disease.

Adult↗
PubMed1992

[Heart sounds--a mathematical transformation of blood pressure? On the origin of heart sounds].

Two main theories exist concerning the origin of the heart sounds. The first proposes that rapid pressure fluctuations cause the cardiac valve leaflets to vibrate and produce the sound. The second theory suggests that sudden pressure perturbations cause the entire cardiohemic mass to vibrate as a whole. In 35 patients (26 men and 9 women, aged 18 to 73) with various heart diseases microtransducer catheters (Millar) were used to simultaneously record aortic pressures and aortic internal phonocardiograms in order to determine if they had a common mode of origin and propagation. The propagation velocities of the first heart sound and the foot of the aortic pressure pulse were found to be similar, 5.24 +/- 0.61 m/s and 5.97 +/- 1.87 m/s respectively (+/- SE). It was possible to derive facsimiles of the aortic internal phonocardiogram by double differentiation of the corresponding aortic pressure pulse and conversely to derive the pressure pulse by double integration of the phonocardiogram. These data support the concept that the low-frequency pressure variations produced by the entire cardiohemic mass, which predominate in the aortic pressure pulse waveforms, are generated and propagated in the same manner as the high-frequency pressure variations, which are the first and second heart sounds.

Adolescent↗
PubMed1984

Audibility of an artificial third heart sound in relation to its frequency, amplitude, delay from the second heart sound and the experience of the observer.

The possibility of detecting synthetic third heart sounds was studied. A special unit was used that added a sound to a previously recorded phonocardiogram. The sound could be changed in frequency, amplitude and delay from the second heart sound. Four groups of observers--cardiologists, residents, nurses and students--listened to 32 random examples. Detection rate increased with experience of the observer (p less than 0.0001) as well as with amplitude (p less than 0.0001), frequency (p less than 0.0001) and delay of the sound (p less than 0.05). The sensitivity was highest among the cardiologists, but the specificity was not different between the groups. Data from this study indicate that the audibility of the third heart sound depends on several important factors. The sound should usually be audible, but variability of results were considerable even among experienced cardiologists. A quantified phonocardiographic recording should be used for validation.

Cardiology↗